This invention relates to tuyeres for metallurgical vessels and, more particularly, to submerged gas tuyeres used in smelting and refining vessels.
Many metallurgical operations are carried out at high temperatures in refractory-lined furnaces provided with one or more submerged gas tuyeres through which oxidizing, reducing or inert gases are supplied to the furnace charge.
As maintenance of the furnace lining and replacement of tuyeres, mainly as a result of erosion and chemical reaction, are major costs, much effort is spent on the design of tuyeres. A common method for alleviating deterioration problems is by cooling the furnace wall and the tuyeres, such as by using cooling fluids, shielding fluids or solid cooling elements, or by using protective sheaths, coatings or the like. Protection is also provided by causing a porous encrustation of solid material to build up at the tip of the tuyere.